IBS and frequent bowel incontinence

I have what appears to be IBS. I have chronic diarrhea like every day a few times a day. I have had numerous GI tests done, including colonoscopy, showing nothing conclusive. I have frequent bowel leakage due to the diarrhea. Its like urge fecal incontinence. I get the urge to go, and I just can't make it. This happens a few times a week. Does this happen to anyone else with IBS?